X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FIPO%2FInlineSimple.cpp;h=42897676418fa9d1803f89ebf5bcaa63d91dcd7f;hb=dd4924c564c7a661b78b604ebf16dfef7aa62b35;hp=0151a2d2ac6dfc191504a886336ee0f1b3f2720a;hpb=ca398dc3989d35e8516489fd163e012133bd41cb;p=oota-llvm.git diff --git a/lib/Transforms/IPO/InlineSimple.cpp b/lib/Transforms/IPO/InlineSimple.cpp index 0151a2d2ac6..42897676418 100644 --- a/lib/Transforms/IPO/InlineSimple.cpp +++ b/lib/Transforms/IPO/InlineSimple.cpp @@ -1,168 +1,103 @@ -//===- FunctionInlining.cpp - Code to perform function inlining -----------===// +//===- InlineSimple.cpp - Code to perform simple function inlining --------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// // // This file implements bottom-up inlining of functions into callees. // //===----------------------------------------------------------------------===// -#include "llvm/Transforms/IPO.h" -#include "llvm/Transforms/Utils/Cloning.h" +#define DEBUG_TYPE "inline" +#include "llvm/CallingConv.h" +#include "llvm/Instructions.h" +#include "llvm/IntrinsicInst.h" #include "llvm/Module.h" -#include "llvm/Pass.h" -#include "llvm/iOther.h" -#include "llvm/iMemory.h" -#include "Support/Statistic.h" -#include +#include "llvm/Type.h" +#include "llvm/Analysis/CallGraph.h" +#include "llvm/Support/CallSite.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Transforms/IPO.h" +#include "llvm/Transforms/IPO/InlinerPass.h" +#include "llvm/Transforms/Utils/InlineCost.h" +#include "llvm/ADT/SmallPtrSet.h" + +using namespace llvm; namespace { - Statistic<> NumInlined("inline", "Number of functions inlined"); - struct FunctionInlining : public Pass { - virtual bool run(Module &M) { - bool Changed = false; - for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) - Changed |= doInlining(I); - ProcessedFunctions.clear(); - return Changed; + class VISIBILITY_HIDDEN SimpleInliner : public Inliner { + // Functions that are never inlined + SmallPtrSet NeverInline; + InlineCostAnalyzer CA; + public: + SimpleInliner() : Inliner(&ID) {} + SimpleInliner(int Threshold) : Inliner(&ID, Threshold) {} + static char ID; // Pass identification, replacement for typeid + int getInlineCost(CallSite CS) { + return CA.getInlineCost(CS, NeverInline); } - - private: - std::set ProcessedFunctions; // Prevent infinite recursion - bool doInlining(Function *F); + float getInlineFudgeFactor(CallSite CS) { + return CA.getInlineFudgeFactor(CS); + } + virtual bool doInitialization(CallGraph &CG); }; - RegisterOpt X("inline", "Function Integration/Inlining"); } -Pass *createFunctionInliningPass() { return new FunctionInlining(); } - - -// ShouldInlineFunction - The heuristic used to determine if we should inline -// the function call or not. -// -static inline bool ShouldInlineFunction(const CallInst *CI) { - assert(CI->getParent() && CI->getParent()->getParent() && - "Call not embedded into a function!"); - - const Function *Callee = CI->getCalledFunction(); - if (Callee == 0 || Callee->isExternal()) - return false; // Cannot inline an indirect call... or external function. - - // Don't inline a recursive call. - const Function *Caller = CI->getParent()->getParent(); - if (Caller == Callee) return false; - - // InlineQuality - This value measures how good of an inline candidate this - // call site is to inline. The initial value determines how aggressive the - // inliner is. If this value is negative after the final computation, - // inlining is not performed. - // - int InlineQuality = 200; // FIXME: This is VERY conservative - - // If there is only one call of the function, and it has internal linkage, - // make it almost guaranteed to be inlined. - // - if (Callee->use_size() == 1 && Callee->hasInternalLinkage()) - InlineQuality += 30000; - - // Add to the inline quality for properties that make the call valueable to - // inline. This includes factors that indicate that the result of inlining - // the function will be optimizable. Currently this just looks at arguments - // passed into the function. - // - for (User::const_op_iterator I = CI->op_begin()+1, E = CI->op_end(); - I != E; ++I){ - // Each argument passed in has a cost at both the caller and the callee - // sides. This favors functions that take many arguments over functions - // that take few arguments. - InlineQuality += 20; +char SimpleInliner::ID = 0; +static RegisterPass +X("inline", "Function Integration/Inlining"); - // If this is a function being passed in, it is very likely that we will be - // able to turn an indirect function call into a direct function call. - if (isa(I)) - InlineQuality += 100; +Pass *llvm::createFunctionInliningPass() { return new SimpleInliner(); } - // If a constant, global variable or alloca is passed in, inlining this - // function is likely to allow significant future optimization possibilities - // (constant propagation, scalar promotion, and scalarization), so encourage - // the inlining of the function. - // - else if (isa(I) || isa(I) || isa(I)) - InlineQuality += 60; - } - - // Now that we have considered all of the factors that make the call site more - // likely to be inlined, look at factors that make us not want to inline it. - // As soon as the inline quality gets negative, bail out. - - // Look at the size of the callee. Each basic block counts as 20 units, and - // each instruction counts as 10. - for (Function::const_iterator BB = Callee->begin(), E = Callee->end(); - BB != E; ++BB) { - InlineQuality -= BB->size()*10 + 20; - if (InlineQuality < 0) return false; - } - - // Don't inline into something too big, which would make it bigger. Here, we - // count each basic block as a single unit. - for (Function::const_iterator BB = Caller->begin(), E = Caller->end(); - BB != E; ++BB) { - --InlineQuality; - if (InlineQuality < 0) return false; - } - - // If we get here, this call site is high enough "quality" to inline. - DEBUG(std::cerr << "Inlining in '" << Caller->getName() - << "', quality = " << InlineQuality << ": " << *CI); - return true; +Pass *llvm::createFunctionInliningPass(int Threshold) { + return new SimpleInliner(Threshold); } - -// doInlining - Use a heuristic based approach to inline functions that seem to -// look good. -// -bool FunctionInlining::doInlining(Function *F) { - // If we have already processed this function (ie, it is recursive) don't - // revisit. - std::set::iterator PFI = ProcessedFunctions.lower_bound(F); - if (PFI != ProcessedFunctions.end() && *PFI == F) return false; - - // Insert the function in the set so it doesn't get revisited. - ProcessedFunctions.insert(PFI, F); - - bool Changed = false; - for (Function::iterator BB = F->begin(); BB != F->end(); ++BB) - for (BasicBlock::iterator I = BB->begin(); I != BB->end(); ) { - bool ShouldInc = true; - // Found a call instruction? FIXME: This should also handle INVOKEs - if (CallInst *CI = dyn_cast(I)) { - if (Function *Callee = CI->getCalledFunction()) - doInlining(Callee); // Inline in callees before callers! - - // Decide whether we should inline this function... - if (ShouldInlineFunction(CI)) { - // Save an iterator to the instruction before the call if it exists, - // otherwise get an iterator at the end of the block... because the - // call will be destroyed. - // - BasicBlock::iterator SI; - if (I != BB->begin()) { - SI = I; --SI; // Instruction before the call... - } else { - SI = BB->end(); - } - - // Attempt to inline the function... - if (InlineFunction(CI)) { - ++NumInlined; - Changed = true; - // Move to instruction before the call... - I = (SI == BB->end()) ? BB->begin() : SI; - ShouldInc = false; // Don't increment iterator until next time - } - } - } - if (ShouldInc) ++I; - } - - return Changed; +// doInitialization - Initializes the vector of functions that have been +// annotated with the noinline attribute. +bool SimpleInliner::doInitialization(CallGraph &CG) { + + Module &M = CG.getModule(); + + for (Module::iterator I = M.begin(), E = M.end(); + I != E; ++I) + if (!I->isDeclaration() && I->hasNote(FN_NOTE_NoInline)) + NeverInline.insert(I); + + // Get llvm.noinline + GlobalVariable *GV = M.getNamedGlobal("llvm.noinline"); + + if (GV == 0) + return false; + + // Don't crash on invalid code + if (!GV->hasInitializer()) + return false; + + const ConstantArray *InitList = dyn_cast(GV->getInitializer()); + + if (InitList == 0) + return false; + + // Iterate over each element and add to the NeverInline set + for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { + + // Get Source + const Constant *Elt = InitList->getOperand(i); + + if (const ConstantExpr *CE = dyn_cast(Elt)) + if (CE->getOpcode() == Instruction::BitCast) + Elt = CE->getOperand(0); + + // Insert into set of functions to never inline + if (const Function *F = dyn_cast(Elt)) + NeverInline.insert(F); + } + + return false; }